Researchers at the Korea Institute of Science and Technology (KIST) have developed a composite shielding material that simultaneously blocks both electromagnetic waves and neutron radiation within a single ultra-thin film thinner than a human hair. The material, created by combining carbon nanotubes (CNTs) and boron nitride nanotubes (BNNTs) within a polymer matrix, addresses a longstanding challenge in spacecraft, nuclear facilities, semiconductor equipment, and advanced medical devices, where both types of radiation are present but have historically required separate shielding layers.
CNTs are highly conductive and function by absorbing and reflecting electromagnetic waves, while BNNTs contain boron atoms that are effective at capturing neutrons. When combined, the two nanotube types spontaneously form a shell structure in which they envelop one another, allowing a single film to address both hazards at once. The composite is then integrated with polydimethylsiloxane (PDMS), a flexible polymer, to produce a material that is both lightweight and stretchable.
In testing, the material achieved electromagnetic wave blocking at a rate of 99.999% and reduced neutron flux by approximately 72%, even at thicknesses below that of a human hair. The material also retains these shielding properties when stretched to more than twice its original length, making it compatible with applications requiring flexibility and conformal coverage.
The research team further demonstrated that the composite can be processed using 3D printing, enabling fabrication into complex geometries. A honeycomb structure produced through this method was found to deliver up to 15% better shielding performance than a flat sheet of equivalent thickness, highlighting the importance of structural design in maximizing material efficiency.
Thermal durability tests confirmed stable performance across a temperature range of -196 degrees C to 250 degrees C, covering the extreme thermal cycling encountered in space operations.
Dr. Joo Yong-ho, who led the research at KIST's Extreme Environment Shielding Materials Research Center, described the result as "a completely new concept in shielding technology – it is as thin as tape and as flexible as rubber, yet simultaneously blocks both electromagnetic waves and radiation." He noted that the work is significant for establishing the domestic production infrastructure required for the space age, and that the team plans to further optimize shielding performance through structural design refinement and pursue industrial applications.
The research team identified target application areas including satellites, space stations, nuclear power facilities, cancer treatment equipment, and wearable protective gear. The ability to replace multiple discrete shielding layers with a single multifunctional film is expected to reduce system mass and structural complexity in these domains.
Research Report:Ultrathin, Stretchable, and 3D-Printable Complementary Nanotubes-Polymer Composites for Multimodal Radiation Shielding in Extreme Environments
